From LedHed's Wiki
General notes about FreeBSD.
Multiple /etc directories
FreeBSD has 2 different /etc folders
/etc /usr/etc
If you can't find the .conf you're looking for try the other etc location.
rc.conf
/etc/rc.conf is where the FreeBSD service/startup settings are set.
Setting Environment Variables
setenv HTTP_PROXY http://192.168.100.1:8080